【摘要】 通过对总谐波畸变率(total harmonic distortion,THD)的分析,证明基于最小THD的多电平脉宽调制(pulse widthmodulation,PWM)电平选择策略的存在。进一步对多相多电平PWM进行THD最优化分析,建立与相数、电平数及单相目标波形的具体形式无关的目标随优PWM算法。将所得结论应用于正圆形目标轨迹,论证空间矢量脉宽调制最优算法和零矢量对称分配方案的本质,揭示多相PWM中谐波注入应遵循的普遍规律。从理论推导、数值仿真和实验3个方面对算法进行检验,检验结果证明了所做结论的理论正确性和应用广泛性。更多还原

【Abstract】 In the paper,the existence of the minimal total harmonic distortion(THD) based multi-level pulse width modulation(PWM) chosen strategies was proved through THD theoretical analysis.Furthermore,the novel targetoptimum-oriented PWM algorithm,which is independent of number of inverter phases or level numbers,and with no relation with the form of curves on any phase,was proposed the first time through the multi-phase-multi-level PWM with minimal THD analysis.Then,this algorithm was applied in circular track case,the essence of optimized space vector pulse width modulation(SVPWM) and equal-distribution policy of zero-vectors was discovered,the universal rules for the harmonic injection in multi-phase PWM was revealed.Finally,the conclusion of this paper was verified by theory,simulation and experiment,which was proved to be correct in both theoretical and application aspects.更多还原